The researchers gave rats coffee with caffeine and decaffeinated coffee for three days and saw that throughout the period, their small intestines had an improved ability to contract, regardless of the level of caffeine content.

They suspected the gut microbiome may also play a role and decided to look at how coffee was affecting bacteria in the gut. To figure this out, they mixed rat poop and coffee in a petri dish and saw that the number of bacteria decreased.

Interestingly, they found that the higher the amount of coffee in the petri dish, caffeinated or not, the fewer microbes were present. They also saw that over three days, the bacteria in the rat's poop had decreased.

More research is needed to determine whether the coffee is eliminating good or bad bacteria, but either way, these findings suggest that the reason coffee makes us poop is likely in part to do with changes to the gut microbiome.

So, what does all this mean for us? Well, experts suggest that we should be pooping one to three times a day ideally, and it's best if our food is actually stimulating the bowel movements. If you have fewer bowel movements or are experiencing pain while trying to poop, then you may be constipated, said Vincent Pedre, M.D., integrative gut health specialist and mbg Collective member, and it may make sense to have some coffee to kick-start some bowel movements.

In fact, the present study highlights the need for more research on whether coffee may be a viable option for constipation after things like abdominal surgery. But before you start guzzling down even more cups of coffee, you'll want to be on the lookout for signs you're already pooping too much, more than three times per day, as this may be a sign of a more significant issue.